(1-cos2x)+sin2x=根号2(sin2x cosπ/4-cos2x sinπ/4)+1

已知tan(x-π/4）=2 求（sin2x+cos2x）/（2cos²x-3sin2x-1) 已知tanx=-4/3,试化简(2+cos2x)/[(根号2)·cos(x-π/4)-sin2x] 已知tan(x-π/4),求(sin2x+2cos2x)/(2cos²x-3sin2x-1)的值 x为第二象限角,sinx=根号15/4求sin(x+π/4)/sin2x+cos2x+1的值 两个个数学证明题1.证明：cos2x+sin2x=√2sin(sin2x+π/4)2.证明：αsinαx+cosαx=√ 化简：2cos2x+2sin^2 x+cos(-x)分之sin2x+sin(π-x)=___________ sin2x+cos2x+2=根号2倍的sin(2x+π/4)+2怎么出来的, Cosx+sinx分之1+sin2x+cos2x=2cos 证明 1.y=cos^4x+sin^4x 求周期 2.y=（sin2x+sin（2x+π/3)）/（ cos2x+cos（2x 已知函数fx=(1+cos2x+sin2x)/sin(x+π/2) 求证1+sin2x-cos2x/1+sin2x+cos2x=tanx 2sin2x+cos2x=1,求2cos^x+sin2x\1+tanx的值